Picture of Micro Drill Press
I shop in thrift stores a lot to find materials for my projects.
On my project list was a drill press to finish home made PCB's.
I found a vintage hobby microscope that is perfect for the job.

Then I bought a rotary tool at Harbor Freight for 7 dollars.
The tool fits very snugly inside a short piece of 1 1/4 PVC sch40 that is modified to replace the original eyepiece.

The base is 4in square. The throat depth is almost 3 inches.
There is no return spring, but the rack and pinion gives plenty of control for drilling.

No mods to the tool are necessary.
But...I couldn't help myself.

The wallwart supplied has a 12v output with barely enough current to turn the motor.
I Googled the motor Part# and found it rated for 24v.
I now run it from an 18v 5A power supply and the performance is more than adequate for the job.
I also added a PWM motor speed controller (that little circuit board on the table).

Works great.

You might get really lucky and find an old microscope at Goodwill, but first I would raid my kid's toy box.
Raid your neighbor's toy box, too.

dudes11 months ago

I have the same rotary tool, I measured the "12v" wall adapter and found it puts out just over 19v. Just in case you're curious. :)

wotboa (author) 1 year ago

See the new improved Micro Drill Press revision A at:


I solved the problems of using a cheap rotary tool.

markey19791 year ago
sorry about being a little impatient, but my question may have been answered. I would put this in the TL;DR category, so please forgive me.

I would first like to say that this is a great instructable. I really like the PVC tool holder. The only problem that I see is the cheap rotary tool.

Do you find there is a lot of runout on the spindle? I have previously purchased one of these tools and cannot say much for it at all. My spindle had about .040" runout...
wotboa (author)  markey19791 year ago

Hiya marky1979

Sorry I haven't been able to reply to comments. Lately I've been using public computers to get online.

I agree that tools made in China are mostly pieces of sh!t. Caveat Emptor.

This cheap rotary tool will work okay IF center marks are pressed into the board before drilling. The bit will find the center and drill without wandering. On my micro drill the runout & slop became unacceptable after just a few months.

So I have updated the drill press to Revision B:
I replaced the rotary tool with a bare 18v DC motor (30,000 rpm!!!) from a cordless drill motor.
I fabricated a new motor mount.
I installed a new collet style chuck.
I extended the control knob shaft.

The drill press now works better than ever (and just a little noisier).

I'm going to update the original Instructable with modifications & pictures, but it may be a little while until I can post it.

This has been one of my favorite tools. It has always worked great, so I spent the time and energy to make a good tool better.


sk8er61 year ago
Hey I got the same tool! I only got it for sanding wood and gutting out plastics for mods, but I didnt know I could double the volts! So you just hooked up 18v 500ma to to the wart end of it and it was ok? I have a ton of PC power supplies I converted out of boredom.
wittmason2 years ago
Does the mini drill press have any side to side "play". I have a dremel drill press currently that likes to wander across the piece I'm drilling - I need to replace it and was considering this route.
psychlones2 years ago
Just to be sure I've read it correctly - you indicated that you run it from an 18v 5A power supply - is that 5 amps or 0.5 amps (500mA)? Thanks for sharing a great idea :-)
wotboa (author)  psychlones2 years ago
Hiya psychlones
These little DC motors use a LOT of current. At no-load the tool uses way less than an amp, but under load the current goes up fast. Three amps should be more than the motor's stall current (my guesstimate). Five amps will give the power supply a little cushion.
wotboa (author)  wotboa2 years ago
P.S. My suggestion? Build a variable linear PS/ 3-30vdc/ 10+ amps. Use a lot of heat sink. It will be your new 'Bench Power Supply'.
Or...buy a switcher on EBay. They got a lot to choose from for under $20.
Add this LM324 PWM speed controller to feed the motor.
Your suggestions are much appreciated and detailed enough to get me headed in the right direction. Thanks very much for taking the time to answer my query. Have a happy!
That is genius!
wotboa (author)  jessyratfink3 years ago
Hi jessyratfink
thanks but its not quite genius.
engineers call it elegant simplicity.

plbwhr wotboa3 years ago
You took the words right out of my mouth: elangant and simple.
TheTinGal3 years ago
I am in love with this. Thank you for sharing!
wotboa (author)  TheTinGal3 years ago
I'm picking your screen name apart.
Could it be 'The Tingle"?
No sir, I apprentice with a tinsmith and have taken it upon myself to come up with a name to associate with the tin things I make and sell. I am 'the tin gal'.
wotboa (author)  TheTinGal3 years ago
Sir? Sir???? This nay be Olde England m'lady. I don't see no sirs in this here room.
Be proud of your craft. The students coming out of college (with degrees) can barely tie their own shoelaces.
take care
wotboa (author)  TheTinGal3 years ago
Thanks TheTinGal, my pleasure
Since I'm just the curious kinda guy, I scanned your profile. Join date is TODAY!
I'm your first hit. What an honor.
Welcome aboard. This is a fun website, many things to learn.
Create some 'thing', post it, & have a blast.

PS This is the first instructable I published
Wow very good. Never would have thought of the whole microscope thing. Nice job man!
jack0023 years ago
I saw this pic of your drill in the "there_fixed_it" website. They must have thought your drill was funny looking. I think its great! I love it. Good thinking.
wotboa (author)  jack0023 years ago
That was me. I posted it there as a kludge.
It looked so good that I published on instructables the next day.
I love it, my only modification would be over sized spinner handle, so i could pretend it was really hard to work, you get top marks from me
wotboa (author)  bobby sissom3 years ago
The only way to make this little beauty hard to work would be to cut off your thumbs.
GpaSteve3 years ago
Very cool, going to have to try this
This is great, I must build one!
wotboa (author) 3 years ago
Nyuk nyuk nyuk!!!!
I just got my own joke!
I named this thing a 'micro' drill press cuz it's smaller than a 'mini' drill press.
Now the full name should be 'Microscope Drill Press'.
Huh? Huh?

Never mind
justbennett3 years ago
This seems like a great way to torture amoebas and paramecium.
ideeman19943 years ago
Thanks for the tip, it's a very clever hack :)

BTW, you're on Hack a Day ;)
wotboa (author)  ideeman19943 years ago
Hi ideeman
On hackaday, too?
Wow, I feel like such a celebrity after just one day. Thank you very much.

I built this thing over a year ago. I use it a lot and have never been disappointed.
At the time I was looking to make a PCB drill press, the only solutions I liked (posted online) involved hinges, springs, expensive components, or some other Rube Goldberg technology.
I will say this (pardon me for not being humble). This is the best DIY PCB drill press I have ever seen.

cj86753 years ago
i got a mini drill press for 5 dollars at a flea market
l8nite3 years ago
that's a COOL tool ! thank you for sharing the idea .
pfred23 years ago
Nice one. A long time ago I tried to drill PCBs I'd made with a Dremel held in my hand. Didn't work for me! Now I have a miniature drill press and it is dead simple. I'm sure your microscope modification helps a lot!
nattyclem3 years ago
I was just wontering about something else to use a microscope for and then I saw this. It is so simple, yet ridicously awesome. I love it.
Just an idea, but if you find the PVC to loos, you could use circlips to hold the drill on.

stone34083 years ago
That is great! I though that this was going to be one of those "look what I did with the special piece that only I have" but the microscope base is widely available. Very cool. Now I have to do this.
wotboa (author)  stone34083 years ago
Hi stone3408
It seemed like a fluke when i found that microscope just when i needed a precision drill press.
This thing works so great you would not believe.
So when you find a cache of a million surplus microscopes for sale you'll let me know, right?
seeya later, partner